Liquid-solid separating apparatus



Feb. 2, 1965 E. F. HANSEN 3,168,033

v LIQUID-SOLIDr 'SEPARATING APPARATUS Filed oct. 1o, 1962 2 sheets-sheet 2 FIG. 49. FIG. 5.

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L mule-WMM 'sul EDWARD F. HANSEN BYM/w United States Patent Oiiice 3,168,033 Patented Feb. 2, 1965 3,168,033 LIQUID-SOLID SEPARATING APPARATUS Edward F. Hansen, P.O. Box 95, Stanton, NJ. Filed Oct. 10, 1962, Ser. No. 229,629 2 Claims. (Cl. loll- 179) This invention relates to a press for separating liquids from solids, and more particularly to an hydraulic cage press for separating castor oil from the castor seed or bean.

Prior equipment ordinarily available for extracting oil from seeds has been either impossible or impractical to automate or, if automated, produced an inferior grade of oil.

One type of extracting mechanism in the latter category is the extrusion press which uses an elongated screw rotating within a cylindrical cage. The screw binds and compacts the castor beans and forces the ground material through a constriction at the discharge end of the cage. The constriction causes pressure on the material to increase to a level where the oil is expressed through slots in the cage. To prevent the oil bearing material from extruding without oil separation, the beans are cooked or heated to a temperature in the range of i90-220 F. in order to coagulate the protein in the endosperm of the beans. This type of extractor yields an inferior grade of oil.

Another type of extracting mechanism is known as the cage press which uses an hydraulic piston to force a ram into a perforated or slotted cylinder called a cage. The cage is charged with beans heated to l40-l70 F.; a lower temperature than is required for the extrusion process. The advancing ram squeezes the oil from the beans which then seeps radially to the perforated cage between the flattened beans. The crude castor oil thus expressed has less suspended solids than the crude oil expressed from the ground beans in an extrusion press, and therefore can be clarified and ltered with a small filter pump and filter press installation. Another advantage of hydraulically expressed castor oil is that it has a low free fatty acid. Still another advantage is that it can be bleached to a brighter color with less carbon black and bleaching clay.

This oil, produced in the hydraulic cage press process and having superior physical and chemical properties, is known as cold pressed castor oil. It commands a higher price and is the preferred grade of castor oil for use in pharmaceuticals, cosmetics, light-colored surface coatings, dielectric oils, hydrogenated and urethane derivatives, and other applications.

Although the cage press produces superior oil, it has not been used widely because cage presses of the prior art are diicult and costly to automate. The basic cage press design is described in the Hubbell Patent No. 697,251. In the Hubbell press it was necessary to remove the cage from the press for feeding beans and discharging cake. Many attempts have been made to automate and improve upon the Hubbell device but, because of the massive structure of the device and the heat and power losses derived therefrom, this has been unsuccessful thus far.

Accordingly, it is an object of this invention to provide a substantially automatic cage press.

Another object is to provide a press that can be operated rapidly and in a substantially continuous manner.

Another object is to provide a cage press having automatic feed and cake discharge mechanisms.

A further object is to provide an hydraulic power system which virtually eliminates contamination of the seed oil by the hydraulic Huid.

A still further object is to provide a unique means for sealing the discharge end of the cage press.

Another object is to provide a press that is inherently safe with all moving parts enclosed within the structure of the press.

Still further objects are to provide a cage press that is simple to erect and maintain; that has a low energy requirement per unit of capacity; that has a low labor requirement per unit of material processed; that has a low capital investment per unti of capacity; `and that produces an oil with superior chemical and physical properties.

The above and other objects are accomplished in accordance with this invention which comprises an elongated perforated cylinder, a charging inlet in the wall of said cylinder adjacent a first end thereof, means for feeding seeds into the inlet, extractor piston means mounted for reciprocal movement within the cylinder, means for reciprocating the piston, inlet cut-off means for automatically opening and closing the inlet in timed relation with the movement of the piston, and gate means adjacent a second end of the cylinder for opening and closing the second end.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description, taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

Referring now to the drawings:

FIG. l is a side-elevational view of the press with parts broken away and parts in section and further showing, diagrammatically, the hydraulic system which opcrates the pistons in the press.

FIG. 2 is a side view of the charging inlet and sliding sleeve with parts broken away and parts in section.

FIG. 3 is a sectional View taken along line 3-3 of FIG. 2.

FIG. 4 is an elevational View of the extraction cylinder showing the feeding operation of the press.

FIG. 5 is an elevational View of the extraction cylinder showing an oil extraction operation of the press.

FIG. 6 is an elevational view of the extraction cylinder showing a cake ejection operation of the press.

FIG. 7 is an elevational view of the extraction cylinder showing a piston retraction operation of the press.

FIG. 8 is a bottom plan view of the tie rod block and gate with the gate shown in the open position.

Referring now to the drawings and more particularly to FIG. l of the drawings, there is shown an elongated perforated extraction cylinder 1t). Cylinder 10 has a smooth internal bore of uniform diameter and a plurality of holes 11 spaced throughout the cylinder wall through which expressed oil flows.

Extraction cylinder 1t) has a charging inlet 12 at the upper end thereof through which beans 13 are fed into the cylinder from hopper 14. Heated beans are stored in hopper 14 and fed by auger 15 to feed pipe 16 and then through charging inlet 12 into the extraction cylinder 18.

At the lower end of cylinder 10, which is the cake discharge end, is a tie rod block 17. Referring to FIG. 7 of the drawings, tie rods 18 are shown passing through tie rod block 17 at the lower end of cylinder 10 and head block 19 of main hydraulic cylinder Ztl at the upper end of cylinder 10. The tie rods are secured to tie rod block 17 and head block 19 and thereby hold cylinder 10 directly to the main cylinder 20 instead of using external columns and cross heads as in the presses of the prior art. For ease of assembly tie rods 18 are threaded at their ends and secured to the tie rod block 17 and head block 19 by nuts 21.

Referring again to FIG. l, head block 19 is supported by bracket 22 and securely maintains main cylinder 20 in axial alignment with cylinder 10. The upper end of main cylinder 20 is supported by head block 23 and bracket 24. A booster cylinder 25 is mounted in axial alignment With main cylinder 20 and cylinder 10. Booster cylinder 25 is supported at its upper end by head block 26 and bracket 27. The booster cylinder piston 28, booster cylinder piston rod 29, main cylinder 30, main cylinder piston rod 31, and the extractor piston 32 are asembled to move as a single unit within the press. Head blocks 19 and 23 contain conventional sealing apparatus to maintain a tight seal on piston rods 29 and 31 to prevent leakage of fluid Vfrom one cylinder to another. This latter structure is important since it is desirable to prevent contamination of the expressed oil by the hydraulic fluid.

The lower end of extraction cylinder is provided with a trough 33 and a drain 34 for collecting and conveying the expressed oil to a storage tank (not shown).

The cake discharge mechanism is illustrated in FIGS. 1 and 8 where numeral 35 designates the discharge gate which is slideably mounted below tie rod block 17. Gate 35 is supported by a retaining plate 36 which is bolted to tie rod block 17 through spacers 37. Gate 35 is Vreciprocated to open and closed positions by piston rod 38 which is actuated by piston 39 within hydraulic cylinder 40. Hydraulic cylinder 40 is supported by brackets 41 and 41a attached to tie rod block 17 and retaining plate 36, respectively, and hydraulic uid is supplied by cylinder 40 through lines 42 and 43 from a source (not shown). When piston 39 is in the FIG. 1 position gate 35 is closed and the pressed cake within cylinder 10 cannot be discharged by the motion of piston 32 downwardly. This enables piston 32 to press the beans and to extract oil therefrom. When piston 39 moves in a direction to the right in FIG. 1 aperture 44 in gate 35 is placed in axial alignment with aperture 45a in tie rod block 17, aperture 45 in retaining plate 36, and the end Vof cylinder 10, and then a portion of the pressed cake may be ejected from cylinder 10 by the movement of piston 32 downwardly.

A trough 46 is provided below gate 35 to collect the ejected cake and to convey it by means of aguer 47 away from the press.

FIGS. l, 2 and 3 illustrate the charging inlet cut-olf mechanism which consists of a sleeve 48 which is slideably mounted within cylinder 10. Sleeve 48 has an inwardly directed llange 49 at the lower end thereof which supports helical spring 50. Spring 50 is a compression spring and tends to force sleeve 48 in a direction away from head block 19. When piston 32 is retracted it contacts sleeve 48 and overcomes the force of spring 50 to withdraw sleeve 48 from over the charging inlet 12. This allows beans to enter cylinder 10 to provide a charge for the next pressing operation. When piston 32 is advanced beyond charging inlet 12 spring 50 forces sleeve 48 axially within cylinder 10 to cover charging inlet 12, as shown in phantom in FIG. 2, and thereby prevent feeding of beans into the cylinder. Stop pin 51 slides in groove 52 in the internal surface of cylinder 10 and abuts a shoulder 53 to thereby limit the axial movement of sleeve 48 within the cylinder. This construction within the cylinder provides an automatic cut-off mechanism for the charging inlet 12 which operates in timed relation with the movement of piston 32. Not only does it provide an automatic cut-olf means, but it provides a means whereby beans may be fed by gravity into cylinder 10 and also provides a means which will positively prevent the feeding of beans behind piston 32.

FIG. 1 illustrates, diagrammatically, a preferred hydraulic system which may be used with this invention. A source of hydraulic fluid is provided at 54 and the piston rod assembly is advanced and retracted by admiting hydraulic fluid from a pumping system 55 to the small diameter booster cylinder 25 through the directional valve 56. The action of the booster cylinder 28 alone will extract between 70 and 80% of the recoverable oil from the beans. By admitting hydraulic oil under pres- :SLIIP ,1.0 the large diameter main cylinder through valve 57 and maintaining it there for a period of time, the piston assembly will slowly advance and extract an additional 10 to 20% of the oil. When valve 57 is turned to the FIG. l position, the ball in conventional check valve 58 is moved against the seat and blocks the flow of hydraulic oil to the lower end of main cylinder 20 through head block 19. To retract the piston assembly the directional valve 56 is positioned to admit hydraulic oil under pressure to the lower end of the booster cylinder 25 through head block 23 and to the pilot line 59 leading to check valve 58. The application of hydraulic pressure to ball check valve 58 lifts the ball olf the seat and permits booster cylinder 25 to retract the piston rod assembly. Retracting the piston rod assembly by using the booster cylinder alone keeps high pressure hydraulic fluid away from the main piston rod seal which is located in head block 19 where a failure would permit hydraulic uid to flow into the extraction cylinder 10 and contarninate the crude oil. The upward movement of piston 30 forces oil out of line 60Yin head block 23 and back to tank 54. The oil is also free to flow back into head block 19 to thereby lubricate piston rod 31 which connects piston 30 and piston 32.

The operation of the hydraulic system will become more apparent with the following discussion of the operation of the overall press.

FIGS. 4 to 7 illustrate the sequence of operation of the press. The operation of the press starts, as illustrated by FIG. 4, with gate 35 in the closed position and a plug or cake 61 of pressed beans in the lower portion of the cylinder 10 directly above gate 35. This plug 61 has been left from the preceding pressing operation and acts as a seal for the following operation. Piston 32 and cut-olf slide 48 are in the retracted position and beans 13 are entering inlet 12 to fill cylinder 10. When extraction cylinder 10 is partially lled, directional valve 56 for booster cylinder 25 is positioned, as shown in FIG. 1, to advance the rod assembly. The advancing extractor piston 32 crushes the beans, as shown in FIG. 5, and causes the extracted oil to seep radially to the holes 11 in cylinder 10. When piston 32 releases the pressure on spring 50, the spring forces cut-off slide 48 axially to a position adjacent charging inlet 12 to stop the flow of beans therethrough. If desired, the above operation may be repeated one or more times until cylinder 10 is nearly fully of partially extracted beans. At this ktime valve 57 is open, as shown in FIG. l, to allow tluid to enter main cylinder 20 and to add its thrust to the piston rod assembly and extractor piston 32. Pressure is maintained on both cylinders until'the optimum quantity of oil is expressed. As shown in FIGS. 1 and 5 the expressed oil merely ows down the outer side of cylinder 10 into trough 33 and is carried olf by pipe 34.

When the desired amount of oil is expressed from the beans, the slide gate 35 is moved to the open position by the action of piston 39 within hydraulic cylinder 40. When aperture 44 is in alignment with aperture 45 of reta'ming plate 36 the piston 32 will eject that portion of the cake that extends below the upper portion of gate 35 when piston 32 is fully extended. The portion of the ejected cake is shown at 62 in FIG. 6 and the portion of the cake that remains in tie rod block 17 and cylinder 10 is shown at 61.

After cake 62 is ejected gate 35 is moved to the closed position and piston 32 is again retracted to thereby retract cut-otf slide 48 to begin a new cycle of operation.

Though the foregoing description shows the press mounted vertically, an inclined installation may be desirable in a building with limited head room. A triple piston and rod lassembly is an inherently rigid structure that, regardless of position, does not place eccentric loads on the seals and cause them to fail prematurely.

The three valves controlling the operation of the press, Valve 56, valve 57, and the conventional directional valve for cylinder 40 (not shown), may be positioned by any suitable means. The cycling flexibility which is inherent to this press and its controls is essential for the economic operation of an oil mill. For example, during a season when bean supplies are low it may be preferable to crush continuously with a long holding period under high pressure to extract the maximum quantity of oil. During a season when beans are in abundant supply, as during harvest, it may be more protable to shorten the press cycle, with a corresponding lower yield of oil, in order to raise the daily crushing capacity. The loss of income from the lower yield of oil caused by the reduced rate of crushing may be offset by a reduction in inventory and storage charges. IThe above discussion illustrates the operational exibility that is possible with this invention. For example, several tamping operations may be performed on a series of small charges fed into the extraction cylinder. The tamping pressures may range from 1000 to 1200 pounds per square inch and may be applied entirely by the booster cylinder. When the main cylinder is actuated a total holding pressure of 5000 pounds per square inch is possible to express the maximum quantity of oil from the beans.

While there has been described what is at present considered `to be the preferred embodiment of this invention, -it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, aimed to cover all such changes and modifications as fall within the true spirit and scope of the invention.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. Apparatus for separating oil from seeds comprising an elongated perforated cylinder, said cylinder having a charging inlet in the cylinder wall spaced from a first end of said cylinder, means for feeding seeds into said inlet, an extractor piston mounted for reciprocal movement within said cylinder, means for reciprocating said piston, a sleeve slidably mounted within said cylinder between said piston and said lirst end, means for biasing said sleeve axially within said cylinder in a direction away from said irst end, stop means for limiting the axial movement of said sleeve adjacent said inlet to close said inlet, said sleeve being retracted toward said first end to open said inlet by contact between said piston and said sleeve during the movement of said piston toward said iirst end and gate means adjacent a second end of said cylinder for opening and closing said second end.

2. Apparatus for separating oil from seeds comprising an elongated perforated cylinder, said cylinder having a charging inlet in the cylinder wall spaced from a first end or" said cylinder, means for feeding seeds into said inlet, an extractor piston mounted for reciprocal movement Within said cylinder, means for reciprocating said piston, a sleeve slidably mounted within said cylinder between said piston and said first end, a spring for biasing said sleeve axially within said cylinder in a direction away from said first end, stop means tor limiting the axial movement of said sleeve adjacent said inlet to close said inlet, said sleeve being retracted toward said first end to open said inlet by contact between said piston and said sleeve during the movement of said piston toward said rst end, gate means operable to open and close a second end of said cylinder, said gate means comprising a plate mounted for reciprocal movement substantially perpendicular to the axis of said cylinder, and means for reciprocating said gate, said piston being reciprocable toward and away from said plate, said piston being spaced from said plate when said piston is fully extended toward said plate and the movement of said piston toward said plate being effective to press said seeds against said plate when said plate is in a closed position and the movement being effective to eject a major portion of pressed seeds from said one end of said cylinder in a direction axially of said cylinder when said plate is in an open position while causing a portion of said pressed seeds to remain in said cylinder between said piston and said one end, whereby said remaining portion in said cylinder forms a plug to prevent leakage lof oil from said one end.

References Cited in the file of this patent UNITED STATES PATENTS 701,882 Holden June l0, 1902 755,126 Furst Mar. 22, 1904 1,071,020 Bartholomew Aug. 26, 1913 1,939,556 Kammer Dec. 12, 1933 2,145,096 Schutz Jan. 24, 1939 2,598,016 Richardson May 27, 1952 2,705,916 Millgard Apr. 12, 1955 2,780,989 Guy Feb. 12, 1957 3,005,403 Van Endert Oct. 24, 1961 FOREIGN PATENTS 40,904 Germany Oct. 8, 1887 195,706 Germany Feb. 24, 1908 

1. APPARATUS FOR SEPARATING OIL FROM SEEDS COMPRISING AN ELONGATED PERFORATED CYLINDER, SAID CYLINDER HAVING A CHARGING INLET IN THE CYLINDER WALL SPACED FROM A FIRST END OF SAID CYLINDER, MEANS FOR FEEDING SEEDS INTO SAID INLET, AN EXTRACTOR PISTON MOUNTED FOR RECIPROCAL MOVEMENT WITHIN SAID CYLINDER, MEANS FOR RECIPROCATING SAID PISTON A SLEEVE SLIDABLY MOUNTED WITHIN SAID CYLINDER BETWEEN SAID PISTON AND SAID FIRST END, MEANS FOR BIASING SAID SLEEVE AXIALLY WITHIN SAID CYLINDER IN A DIRECTION AWAY FROM SAID FIRST END, STOP MEANS FOR LIMITING THE AXIAL MOVEMENT OF SAID SLEEVE ADJACENT SAID INLET TO CLOSE SAID INLET, SAID SLEEVE BEING RETRACTED TOWARD SAID FIRST END TO OPEN SAID INLET BY CONTACT BETWEEN SAID PISTON AND SAID SLEEVE DURING THE 